Multisig.
Collaborative custody, compared.
Multisig means multiple signatures required to move Bitcoin. It eliminates the single point of failure of a single seed phraseseed phraseThink of it as the combination to a bank vault that exists only in your head: 12 or 24 specific words in a specific order. Anyone who copies the combination opens the vault. The bank has no copy. There is no locksmith, no reset, no customer service. Lose the words, lose the Bitcoin.Full definition. Here is how the major collaborative-custody solutions compare: Casa, Unchained, Nunchuk, Liana, and Sparrow DIY.
Single-signature wallets have a single point of failure: lose the seed, lose the coins. Multisig requires N-of-M signatures (e.g. 2-of-3) to move funds. Casa and Unchained hold one of your keys for recovery support; Nunchuk, Liana, and Sparrow DIY are fully self-managed. The right solution depends on whether you want a recovery partner or full sovereignty, and how much technical work you want to do.
Section 1 · What multisig is
Standard Bitcoin wallets use single-signature (singlesig): one private keyprivate keyA long secret code that proves you are the rightful owner of a chunk of Bitcoin. Anyone who copies the code can spend the Bitcoin. Wallets usually display it as 12 or 24 ordinary English words you can write on paper.Full definition signs every transaction. Lose that key (or the seed phrase that produces it), lose the Bitcoin.
Multisig requires a configurable threshold of multiple keys to sign. The most common configuration is 2-of-3: three keys exist, any two can sign.
Why it matters
- Lose one key, the funds are still recoverable with the other two.
- One key getting stolen does not let an attacker move funds.
- Geographic distribution (different cities or countries) protects against local disasters.
- Inheritance becomes easier: family members hold backup keys without having full custody during your lifetime.
Section 2 · Casa
2-of-3 or 3-of-5 multisig. Casa holds one key. The other keys live on your devices and hardware wallets. If you lose a key, Casa helps recover.
- Trade-off: Casa has one of your keys. They cannot move funds alone (they are one of N), but they are a counterparty.
- Best for: people who want multisig without full technical setup.
- Subscription-based pricing.
verify×DON'T TRUST, VERIFYClaim: Casa offers 2-of-3 and 3-of-5 multisig with one Casa-held key.Verify at: keys.casa ↗Plans, pricing, and key-distribution details change. Confirm before subscribing.
Section 3 · Unchained
2-of-3 multisig. Unchained holds one key in a collaborative model. More institutional-grade than Casa.
- Offers IRAIndividual Retirement Account (IRA)A personal retirement savings account with tax advantages. Two main types: Traditional (tax now, pay later) and Roth (pay now, tax-free forever).Full definition products with Bitcoin in multisig custody (a unique product in the US retirement-account market).
- Concierge onboarding.
- Higher minimum balances and pricing tier than Casa for premium services.
verify×DON'T TRUST, VERIFYClaim: Unchained offers 2-of-3 collaborative custody and Bitcoin IRA products.Verify at: unchained.com ↗Verify current product lineup and IRA terms before opening an account.
Section 4 · Nunchuk
Software for self-managed multisig. No third-party key holders.
- You manage all keys across hardware wallets and mobile devices.
- Most sovereign approach. Most complex.
- Mobile-first interface; desktop also available.
- Optional collaborative coordination layer (Nunchuk Premier) for shared multisigs across family or business partners.
verify×DON'T TRUST, VERIFYClaim: Nunchuk supports self-managed multisig with no third-party key holders by default.Verify at: nunchuk.io ↗Open-source. Codebase is on GitHub.
Section 5 · Liana
Open-source multisig with timelocked recovery.
- A backup key can move funds if the primary key is not used for a defined period.
- This creates a recovery path without a third party.
- Useful for inheritance or for protecting against your own key-management mistakes.
- More technical setup. Built by Wizardsardine.
verify×DON'T TRUST, VERIFYClaim: Liana supports timelocked multisig recovery without a third-party custodian.Verify at: github.com/wizardsardine/liana ↗Open-source. Source available on GitHub.
Section 6 · Sparrow Wallet DIY
Create your own multisig using Sparrow Wallet with multiple hardware wallets.
- Most sovereign. Most complex.
- You hold all keys.
- Requires technical comfort with multisig coordination.
- Free (only the cost of hardware wallets).
- Sparrow's documentation walks through the exact setup with 2-of-3 examples.
For the deeper technical walk-through, see Multisig Deep Dive.
- Casa · keys.casa.
- Unchained · unchained.com.
- Nunchuk · nunchuk.io.
- Liana (Wizardsardine) · github.com/wizardsardine/liana.
- Sparrow Wallet multisig documentation · sparrowwallet.com/docs/multisig.